Knee Arthritis Pain: What the MRI, the Brain, and the Muscles Each Tell You — Muscle IQ in Orem

You have been told it is arthritis. Maybe the word was "bone on bone." The stairs at church take longer than they used to, and a walk around your Orem neighborhood ends with an ache that lingers into the evening. It is natural to assume the picture of the joint explains it all.

Research suggests knee arthritis pain has at least three sides to it: what the scan shows, what the nervous system is doing with the pain signal, and how well the muscles around the knee are working. Each one tells you something different, and the good news is that more than one of them can change.

What the MRI tells you

An MRI shows structure. It can show worn cartilage, a meniscus tear, or fluid in the bone.

What a scan cannot show is how much of your pain comes from those findings. In a 2020 study, researchers scanned 230 knees in adults who reported essentially no knee problems. About 97 percent of those pain-free knees had at least one abnormal finding, roughly 30 percent had a meniscal tear, and more than 60 percent had cartilage changes. The authors concluded that a scan should not stand alone and that diagnosis should rest mainly on your history and a hands-on exam.

The MRI matters. It is just not the whole verdict on your knee.

What the brain tells you

Your nervous system has a built-in way to turn pain signals down, a kind of pain off-switch. A 2025 review that pooled 19 studies found that, on average, people with knee osteoarthritis (the most common kind of knee arthritis) had a weaker off-switch than people without it. Their spinal cords also tended to amplify repeated pain signals more. The authors rated the certainty of that evidence as very low, so it is a pattern worth knowing about, not a final answer.

In a 2021 study of 107 people with knee osteoarthritis, those with more cartilage damage on X-ray sometimes reported less pain, and their brains showed signs of extra braking activity. The researchers suggest the brain may be buffering the pain. The study could not prove cause and effect, but it is one more sign that pain and joint damage do not move in lockstep. The nervous system sits in the middle, deciding how much gets through.

What the muscles tell you

Pain turns down what we call the muscle tone dial, how strongly your nervous system tells a muscle to fire.

In a 2011 experiment, healthy volunteers had a brief, temporary knee pain created in the lab with a salt-water injection. Their thigh strength dropped by about 5 to 15 percent, and the more it hurt, the more strength they lost. Those were healthy people with temporary pain, not people with arthritis, but it shows that pain alone can switch muscles down.

That matters because weak muscles do not protect a joint. Strong muscles do. When the muscles around your knee go offline, neighboring muscles overwork, and more strain lands on tissue that was already irritated. Pain causes muscle weakness, and muscle weakness causes pain. You can read more about muscle inhibition, the idea that a muscle can be switched down even when nothing is wrong with the muscle itself.

Putting the three together at Muscle IQ

The MRI shows the orthopedic surgeon where to put the scalpel. Muscle weakness shows the physical therapist where to treat.

At Muscle IQ in Orem, care starts with a long, hands-on evaluation. We test strength muscle by muscle, including muscles that do not hurt, and ask what is turning your muscle tone down. Then we treat and test again, because a muscle that tests stronger after treatment tells us we are on the right track. You can see how we approach knee pain at Muscle IQ.

There is good reason for hope. In a 2000 randomized trial of 83 people with knee osteoarthritis, a course of hands-on physical therapy combined with exercise improved walking distance and pain, stiffness, and function at 8 weeks, and the gains were still there at one year. One small trial cannot promise the same result for everyone, but it supports trying a thorough course of physical therapy first.

What this does not mean

Arthritis in your knee is not imaginary, and this is not a reason to ignore your scan or your doctor. Decisions about injections or surgery belong to you and your physician, and this post is not medical advice for your knee. A knee that suddenly swells, locks, or gives way should be checked promptly.

What it does mean is that the picture of your joint is only one of three stories. The nervous system and the muscles can change, and that is where physical therapy does its work. If you live in Orem or anywhere in Utah County and knee arthritis is keeping you off the trail or the stairs, you can get better. Strength is coming.

If you have an MRI or X-ray report, bring it to your first visit.

Take control of your health today by calling Muscle IQ at (801) 310-0851 to schedule your first appointment.

Learn more at MuscleIQ.com.